package com.uptech.homer.util;


/**
 * 用于提供与字节计算相关的工具方法
 *
 * @author lei
 */
public class ByteUtils {

    /* CRC-16/IBM： 多项式:X16+X15+X2+1, 生成码为 0x8005. */
    private static final int[] CRC16Table = new int[]{0x0000, 0x8005, 0x800f, 0x000a, 0x801b, 0x001e, 0x0014, 0x8011, 0x8033, 0x0036, 0x003c, 0x8039, 0x0028, 0x802d, 0x8027, 0x0022, 0x8063, 0x0066, 0x006c, 0x8069, 0x0078, 0x807d, 0x8077, 0x0072, 0x0050, 0x8055, 0x805f, 0x005a, 0x804b, 0x004e, 0x0044, 0x8041, 0x80c3, 0x00c6, 0x00cc, 0x80c9, 0x00d8, 0x80dd, 0x80d7, 0x00d2, 0x00f0, 0x80f5, 0x80ff, 0x00fa, 0x80eb, 0x00ee, 0x00e4, 0x80e1, 0x00a0, 0x80a5, 0x80af, 0x00aa, 0x80bb, 0x00be, 0x00b4, 0x80b1, 0x8093, 0x0096, 0x009c, 0x8099, 0x0088, 0x808d, 0x8087, 0x0082, 0x8183, 0x0186, 0x018c, 0x8189, 0x0198, 0x819d, 0x8197, 0x0192, 0x01b0, 0x81b5, 0x81bf, 0x01ba, 0x81ab, 0x01ae, 0x01a4, 0x81a1, 0x01e0, 0x81e5, 0x81ef, 0x01ea, 0x81fb, 0x01fe, 0x01f4, 0x81f1, 0x81d3, 0x01d6, 0x01dc, 0x81d9, 0x01c8, 0x81cd, 0x81c7, 0x01c2, 0x0140, 0x8145, 0x814f, 0x014a, 0x815b, 0x015e, 0x0154, 0x8151, 0x8173, 0x0176, 0x017c, 0x8179, 0x0168, 0x816d, 0x8167, 0x0162, 0x8123, 0x0126, 0x012c, 0x8129, 0x0138, 0x813d, 0x8137, 0x0132, 0x0110, 0x8115, 0x811f, 0x011a, 0x810b, 0x010e, 0x0104, 0x8101, 0x8303, 0x0306, 0x030c, 0x8309, 0x0318, 0x831d, 0x8317, 0x0312, 0x0330, 0x8335, 0x833f, 0x033a, 0x832b, 0x032e, 0x0324, 0x8321, 0x0360, 0x8365, 0x836f, 0x036a, 0x837b, 0x037e, 0x0374, 0x8371, 0x8353, 0x0356, 0x035c, 0x8359, 0x0348, 0x834d, 0x8347, 0x0342, 0x03c0, 0x83c5, 0x83cf, 0x03ca, 0x83db, 0x03de, 0x03d4, 0x83d1, 0x83f3, 0x03f6, 0x03fc, 0x83f9, 0x03e8, 0x83ed, 0x83e7, 0x03e2, 0x83a3, 0x03a6, 0x03ac, 0x83a9, 0x03b8, 0x83bd, 0x83b7, 0x03b2, 0x0390, 0x8395, 0x839f, 0x039a, 0x838b, 0x038e, 0x0384, 0x8381, 0x0280, 0x8285, 0x828f, 0x028a, 0x829b, 0x029e, 0x0294, 0x8291, 0x82b3, 0x02b6, 0x02bc, 0x82b9, 0x02a8, 0x82ad, 0x82a7, 0x02a2, 0x82e3, 0x02e6, 0x02ec, 0x82e9, 0x02f8, 0x82fd, 0x82f7, 0x02f2, 0x02d0, 0x82d5, 0x82df, 0x02da, 0x82cb, 0x02ce, 0x02c4, 0x82c1, 0x8243, 0x0246, 0x024c, 0x8249, 0x0258, 0x825d, 0x8257, 0x0252, 0x0270, 0x8275, 0x827f, 0x027a, 0x826b, 0x026e, 0x0264, 0x8261, 0x0220, 0x8225, 0x822f, 0x022a, 0x823b, 0x023e, 0x0234, 0x8231, 0x8213, 0x0216, 0x021c, 0x8219, 0x0208, 0x820d, 0x8207, 0x0202};

    /******************************************************
     * 函数名称:CRC16 输 入:pszBuf 要校验的数据 unLength 校验数据的长 输 出:校验值 功 能:查表法计算CRC16
     * （美国标准-0x8005）
     *******************************************************/
    public static short CRC16_TABLE(byte[] aData,
                                    int aSize) {
        short nAccum = 0;

        for (int i = 0; i < aSize; i++)
            nAccum = (short) ((nAccum << 8) ^ CRC16Table[((nAccum >>> 8) ^ aData[i]) & 0x00FF]);

        return nAccum;
    }

    /**
     * 计算给定数据的检验和
     *
     * @param data
     *
     * @return
     */
    public static int checkSum16(byte[] data) {
        return checkSum16(data, null, 0, data.length);
    }

    /**
     * 计算给定数据的检验和
     *
     * @param data    要计算校验和的数据内容
     * @param key     密钥
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static int checkSum16(byte[] data,
                                 byte[] key,
                                 int fromIdx,
                                 int toIdx) {

        int tSum = 0;

        for (int i = fromIdx, s = data.length; i < s && i < toIdx; i++) {
            tSum += (short) data[i] & 0xff;
        }

        // 密钥
        if (key != null && key.length > 0) {
            for (int i = 0; i < key.length; i++) {
                tSum += (short) key[i] & 0xff;
            }
        }

        return (tSum >> 16) + (tSum & 0xffff);
    }

    /**
     * 计算给定数据的检验码(异或)
     *
     * @param data
     *
     * @return
     */
    public static short checkXOR(final byte[] data) {
        return checkXOR(data, null, 0, data.length);
    }

    /**
     * 计算给定数据的检验码(异或)
     *
     * @param data    要计算异或校验码的数据内容
     * @param key     密钥
     * @param fromIdx 起始索引(含)
     * @param toIdx   截止索引(不含)
     *
     * @return
     */
    public static short checkXOR(final byte[] data,
                                 final byte[] key,
                                 int fromIdx,
                                 int toIdx) {

        short tVal = 0x0;

        for (int i = fromIdx, s = data.length; i < s && i < toIdx; i++) {
            tVal ^= data[i] & 0xFF;
        }

        // 密钥
        if (key != null && key.length > 0) {
            for (int i = 0; i < key.length; i++) {
                tVal ^= key[i] & 0xFF;
            }
        }

        return tVal;
    }

    /**
     * 将给定的字节数组转换为16进制字符串形式
     *
     * @return
     */
    public static String getHexByteString(final short[] dataBytes) {

        StringBuffer strBuf = new StringBuffer();
        if (dataBytes != null && dataBytes.length > 0) {
            for (Short data : dataBytes) {
                strBuf.append(String.format("%02X", data));
            }
        }

        return strBuf.toString();
    }

    /**
     * 将给定的字节数组转换为16进制字符串形式
     *
     * @return
     */
    public static String getHexByteString(final byte[] dataBytes) {

        StringBuffer strBuf = new StringBuffer();
        if (dataBytes != null && dataBytes.length > 0) {
            for (byte data : dataBytes) {
                strBuf.append(String.format("%02X", data));
            }
        }

        return strBuf.toString();
    }

    /**
     * 将给定的整数值转换为字节数组；遵循小端模式
     *
     * @return
     */
    public static byte[] getBytes(int intVal,
                                  byte[] valBytes) {

        for (int i = 0; valBytes != null && i < valBytes.length; i++) {
            valBytes[i] = (byte) ((intVal >>> (8 * i)) & 0xFF);
        }

        return valBytes;
    }

    /**
     * 将给定的double转换为字节数组；遵循小端模式
     */
    public static void getBytes(double douVal,
                                byte[] valBytes) {
        long l = Double.doubleToLongBits(douVal);
        for (int i = 0; valBytes != null && i < 4; i++) {
            valBytes[i] = new Long(l).byteValue();
            l = l >> 8;
        }
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循小端模式
     */
    public static int getInt(byte[] data) {

        if (data == null) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        return getInt(data, 0, data.length);
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循小端模式
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static int getInt(byte[] data,
                             int fromIdx,
                             int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid");
        }
        if (toIdx - fromIdx > 4) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        int intVal = 0x0;

        // 判断是否是负数
        boolean isNegative = ((data[toIdx - 1] & 0x80) == 0x80);

        // 负数采用补码算法
        if (isNegative) {

            for (int i = fromIdx; i < toIdx && i < fromIdx + 4; i++) {
                intVal ^= (~data[i] & 0xFF) << (8 * (i - fromIdx));
            }
            intVal = (intVal + 1) * -1;
        }

        // 正数直接返回原码
        else {

            for (int i = fromIdx; i < toIdx && i < fromIdx + 4; i++) {
                intVal ^= (data[i] & 0xFF) << (8 * (i - fromIdx));
            }
        }

        return intVal;
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循大端模式
     *
     * @param data
     *
     * @return
     */
    public static int getInt4Bigendian(byte[] data) {

        if (data == null) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        return getInt4Bigendian(data, 0, data.length);
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循大端模式
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static int getInt4Bigendian(byte[] data,
                                       int fromIdx,
                                       int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid");
        }
        if (toIdx - fromIdx > 4) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        int intVal = 0x0;

        // 判断是否是负数
        boolean isNegative = ((data[fromIdx] & 0x80) == 0x80);

        // 负数采用补码算法
        if (isNegative) {

            for (int i = fromIdx; i < toIdx && i < fromIdx + 4; i++) {
                intVal ^= (~data[i] & 0xFF) << (8 * (toIdx - 1 - i));
            }
            intVal = (intVal + 1) * -1;
        }

        // 正数直接返回原码
        else {

            for (int i = fromIdx; i < toIdx && i < fromIdx + 4; i++) {
                intVal ^= (data[i] & 0xFF) << (8 * (toIdx - 1 - i));
            }
        }

        return intVal;
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循小端模式
     */
    public static long getUnsignedInt(byte[] data) {

        if (data == null) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        return getUnsignedInt(data, 0, data.length);
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循小端模式
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static long getUnsignedInt(byte[] data,
                                      int fromIdx,
                                      int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid:data:" + data.length + ",fromIdx:" + fromIdx + ",toIdx:" + toIdx);
        }
        if (toIdx - fromIdx > 4) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        int intVal = 0x0;
        for (int i = fromIdx; i < toIdx && i < fromIdx + 4; i++) {
            intVal ^= (data[i] & 0xFF) << (8 * (i - fromIdx));
        }

        return intVal & 0xFFFFFFFFL;
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循大端模式
     *
     * @param data
     *
     * @return
     */
    public static long getUnsignedInt4Bigendian(byte[] data) {

        if (data == null) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        return getUnsignedInt4Bigendian(data, 0, data.length);
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循大端模式
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static long getUnsignedInt4Bigendian(byte[] data,
                                                int fromIdx,
                                                int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid");
        }
        if (toIdx - fromIdx > 4) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        int intVal = 0x0;
        for (int i = fromIdx; i < toIdx && i < fromIdx + 4; i++) {
            intVal ^= (data[i] & 0xFF) << (8 * (toIdx - 1 - i));
        }

        return intVal & 0xFFFFFFFFL;
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循小端模式
     */
    public static short getShort(byte[] data) {

        if (data == null) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        return getShort(data, 0, data.length);
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循小端模式
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static short getShort(byte[] data,
                                 int fromIdx,
                                 int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid");
        }
        if (toIdx - fromIdx > 2) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        short intVal = 0x0;

        // 判断是否是负数
        boolean isNegative = ((data[toIdx - 1] & 0x80) == 0x80);

        // 负数采用补码算法
        if (isNegative) {

            for (int i = fromIdx; i < toIdx && i < fromIdx + 2; i++) {
                intVal ^= (~data[i] & 0xFF) << (8 * (i - fromIdx));
            }
            intVal = (short) ((intVal + 1) * -1);
        }

        // 正数直接返回原码
        else {

            for (int i = fromIdx; i < toIdx && i < fromIdx + 2; i++) {
                intVal ^= (data[i] & 0xFF) << (8 * (i - fromIdx));
            }
        }

        return intVal;
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循大端模式
     *
     * @param data
     *
     * @return
     */
    public static short getShort4Bigendian(byte[] data) {

        if (data == null) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        return getShort4Bigendian(data, 0, data.length);
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循大端模式
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static short getShort4Bigendian(byte[] data,
                                           int fromIdx,
                                           int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid");
        }
        if (toIdx - fromIdx > 2) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        short intVal = 0x0;

        // 判断是否是负数
        boolean isNegative = ((data[fromIdx] & 0x80) == 0x80);

        // 负数采用补码算法
        if (isNegative) {

            for (int i = fromIdx; i < toIdx && i < fromIdx + 2; i++) {
                intVal ^= (~data[i] & 0xFF) << (8 * (toIdx - 1 - i));
            }
            intVal = (short) ((intVal + 1) * -1);
        }

        // 正数直接返回原码
        else {

            for (int i = fromIdx; i < toIdx && i < fromIdx + 2; i++) {
                intVal ^= (data[i] & 0xFF) << (8 * (toIdx - 1 - i));
            }
        }

        return intVal;
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循小端模式
     */
    public static int getUnsignedShort(byte[] data) {

        if (data == null) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        return getUnsignedShort(data, 0, data.length);
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循小端模式
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static int getUnsignedShort(byte[] data,
                                       int fromIdx,
                                       int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid");
        }
        if (toIdx - fromIdx > 2) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        short intVal = 0x0;
        for (int i = fromIdx; i < toIdx && i < fromIdx + 4; i++) {
            intVal ^= (data[i] & 0xFF) << (8 * (i - fromIdx));
        }

        return intVal & 0xFFFF;
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循大端模式
     *
     * @param data
     *
     * @return
     */
    public static int getUnsignedShort4Bigendian(byte[] data) {

        if (data == null) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        return getUnsignedShort4Bigendian(data, 0, data.length);
    }

    /**
     * 从给定的数组缓存中获取整数值；遵循大端模式
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static int getUnsignedShort4Bigendian(byte[] data,
                                                 int fromIdx,
                                                 int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid");
        }
        if (toIdx - fromIdx > 2) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        short intVal = 0x0;
        for (int i = fromIdx; i < toIdx && i < fromIdx + 4; i++) {
            intVal ^= (data[i] & 0xFF) << (8 * (toIdx - 1 - i));
        }

        return intVal & 0xFFFF;
    }

    /**
     * 从给定的数组缓存中获取片断；
     *
     * @param data
     * @param fromIdx
     * @param toIdx
     *
     * @return
     */
    public static byte[] getRange(byte[] data,
                                  int fromIdx,
                                  int toIdx) {

        if (data == null || fromIdx > toIdx || toIdx > data.length) {
            throw new IllegalArgumentException("arguments is invalid");
        }

        byte[] range = new byte[toIdx - fromIdx];

        System.arraycopy(data, fromIdx, range, 0, toIdx - fromIdx);

        return range;
    }

    public static byte[] getRangeConvert(byte[] data,
                                         int fromIdx,
                                         int toIdx) {
        byte[] source = getRange(data, fromIdx, toIdx);
        return getRangeConvert(source);
    }

    public static byte[] getRangeConvert(byte[] source) {
        byte[] target = new byte[source.length];
        for (int i = source.length - 1, j = 0; i > -1; i--, j++) {
            target[j] = source[i];
        }
        return target;
    }

    /**
     * 使用给定的源数据来顺序填充目标数组
     *
     * @param dest
     * @param srcArys
     *
     * @return
     */
    public static byte[] fill(byte[] dest,
                              byte[]... srcArys) {
        return fill(dest, 0, srcArys);
    }

    /**
     * 使用给定的源数据来顺序填充目标数组
     *
     * @param dest
     * @param offsetIdx
     * @param srcArys
     *
     * @return
     */
    public static byte[] fill(byte[] dest,
                              int offsetIdx,
                              byte[]... srcArys) {

        if (dest != null && srcArys != null && srcArys.length > 0) {

            for (int i = 0, copiedDataLength = 0; i < srcArys.length; i++) {

                if (srcArys[i] != null) {
                    System.arraycopy(srcArys[i], 0, dest, offsetIdx + copiedDataLength, srcArys[i].length);
                    copiedDataLength += srcArys[i].length;
                }
            }
        }

        return dest;
    }

    /**
     * int 转换成byte数组
     *
     * @param i 所要转换的int 由高位到低位
     *
     * @return byte数组
     */
    public static byte[] shortToByte(short number) {
        byte[] b = new byte[2];
        b[0] = (byte) (number >>> 8 & 0x00FF);
        b[1] = (byte) (number >>> 0 & 0x00FF);
        return b;
    }

    /**
     * Bit转Byte
     */
    public static byte BitToByte(String byteStr) {
        int re, len;
        if (null == byteStr) {
            return 0;
        }
        len = byteStr.length();
        if (len == 8) {
            if (byteStr.charAt(0) == '0') {// 正数
                re = Integer.parseInt(byteStr, 2);
            } else {// 负数
                re = Integer.parseInt(byteStr, 2) - 256;
            }
            return (byte) re;
        } else {
            return 0;
        }
    }

}
